Today most multi dose inhalators used for treatment of diseases in the bronchial area have no dose indicating device or have a device only indicating when the storage compartment is empty.
There is a strong desire among the users of such inhalators, patients as well as treating doctors and especially among parents having children using dry powder inhalators, that the inhalators should be provided with dose a indicating device indicating each and every dose as well as the number of doses fed from the storage of the medicament in order to be able to see how many doses are left in the inhalator. This could also be used to determine how many doses have been fed during a certain period of time in order to establish the correct form of therapy.